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Bob Engelhardt

wrote:
I have a treadmill motor on my drill press. To me a drill press
without a variable speed motor would be as unhandy as an auto with
hand crank start. ...

I have a 3 ph & VFD on mine, but I agree about its usefulness. I
advocate for their use regularly.

But the speed can be a problem. Some treadmill motors run more slowly,
e.g., 3000 rpm, but if you have one that runs 7000 and your drill press
is pullyed for a 1725 motor, then you have to cut the speed (& hp) by 4
just to get the same speeds. Then if your drill is pullyed for a lowest
speed of 300 rpm, e.g., and you want to run at 60 rpm, as I do when
tapping, you cut the speed & hp by another factor of 5, you're down to
1/20 of the rated hp. E.g., 1/10 hp from a rated 2 hp , 7000 rpm motor.

Actually, now that I think about, that's not too bad. I run mine at 5
Hz to get 60 rpm, so I'm getting 1/12 of rated hp, which is 1. So I'm
getting 1/12 hp at lowest speed & it's not a problem!

So, I guess that I've got to say to the OP: "Go ahead, use it".

I know when I'm mistaken,
Bob